Dine room breakfast on Carnival offers a few items not available from room service or the buffet like eggs benedict and lox/cream cheese. On this line the menu is the same every day so go ahead and try it a day or 2 to see which you prefer. The buffet has some variation: pancakes today, french toast tomorrow. Room service is a very limited menu w/ no write-ins or changes from day to day. If you want you can get fruit, juice, drink and rolls earlier and then go on to a "full" breakfast elsewhere aboard. This is just 1 example of why many people put on 5-10 lb on a 7 day cruise.